My invention relates to an improvement in a Multiple Stage Flexible Bumper for a highway vehicle using multiple stage compression springs mounted to the front or rear of the vehicle so that it will operate to absorb the energy of a collision, to offer "crash-worthiness" and to help protect the occupants from death or injury and help prevent the vehicle from unnecessary damage in a collision.
With the ever-increasing use of express highways and the high cruising speed of modern automobiles plus the increased number of vehicles on the roads, there is a steady increase in traffic collisions with many deaths and serious injuries due to high speed collision with a barrier or headon collision into an oncoming vehicle. One can hardly read a newspaper or watch the news on television without seeing a head-on collision of an automobile resulting in fatalities or injuries.
Insurance records show that the new so-called 5 MPH metal bumpers with hydraulic cylinders to allow 3 inches movement upon impact, cost more to repair than the old style bumpers.
A recent study made by the U.S. Department of Transportation "shows that 5 MPH bumpers reduce over-all property damage by 5 to 10%, while 10 MPH bumpers would cut property damage by nearly 50%". Ref.: Automotive News, 8-30-76.
Another study made by the U.S.D.O.T. shows: --"Car accidents cost $ 38 billion a year". Ref.: Associated Press 3-17-77. It is an object of my invention to withstand impacts comfortably, without injury or damage as follows: 20 MPH into another car, 10 MPG into a rigid barrier, 10 MPH corner or side impact and a lateral absorption stroke of approximately 5 to 10" and a longitudinal absorption stroke of approximately 5 to 10".
It is another object of my invention to provide the bumper bar 360.degree. free, unencumbered movement around the longitudinal mounting axis on the frame of the vehicle to prevent bent frames, broken welds, dented sheet metal and other damage caused by various angular collisions in the front or rear of the motor vehicle.
It is another object of my invention to provide added resistance to collision forces through telescoping helper springs that compress in stages as the bumper bar moves back against them.
It is another object of my invention to use conventional size springs which are in mass production, inexpensive and light in weight rather than an extra large single spring on each side which would be unconventional in size, too heavy and too rigid for slow speed collisions such as occur in parking lots.
It is still another object of my invention to provide a flexible filler panel to cover the springs and fill the gap between the bumper bar and car body for aesthetics purposes.